Enter the length and width of the aperture and the thickness of the stencil into the calculator to determine the stencil area ratio.

Stencil Area Ratio Formula

The following equation is used to calculate the Stencil Area Ratio.

SAR = [(L*W)/2*(L+W)*T]
  • Where SAR is the stencil area ration
  • L is the length of the aperture
  • W is the width of the aperture
  • T is the thickness of the stencil

What is a Stencil Area Ratio?


A stencil area ratio measures the area beneath the stencil aperture opening relative to the area of the inside aperture wall.

How to Calculate Stencil Area Ratio?

Example Problem:

The following example outlines the steps and information needed to calculate Stencil Area Ratio.

First, determine the length of the aperture. In this example, the length is 5 inches.

Next, determine the width of the aperture. In this case, the width is 3 inches.

Next, determine the stencil thickness. This stencil has a thickness of 1 inch.

Finally, calculate stencil area ratio using the formula above:

SAR = [(L*W)/2*(L+W)*T]

SAR = [(5*3)/(2*(5+3)*1)]

SAR = .9375